[DFTB-Plus-User] DOS Fermi Energy problem

[Ezgi Erdogan]

Sorry for band.dat miss typing but still my question is the same.. while
sending e-mail i wrote wrong.

2009/8/20 Ezgi Erdogan <ezgierdo at gmail.com>

> Dear users,
> I would like to ask you the density of states (DOS) graphics. I have
> trouble around fermi level.
>
> 1- Proper Density and Unitcell Geometry
> a) dftb_in_dos.hsd input file is:
> ///////////////////////////////////////////////
> Geometry = GenFormat {
> <<<"dftb_in.geometry.gen"
> }
>
> Hamiltonian = DFTB {
>   SCC = No
>   SCCTolerance = 1e-5
>   MaxAngularMomentum = {
>     C = "p"
>     H = "s"
>   }
>  SlaterKosterFiles = {
>     C-C = ""
>     C-H = ""
>     H-C = ""
>     H-H = ""
>
>    }
> PolynomialRepulsive = SetForAll{No}
>
>   KPointsAndWeights = SupercellFolding {
>     8   0     0
>     0   1     0
>     0   0     1
>     0.5 0.0  0.0
>   }
> }
>
>
> b) dftb_in_dos.geometry.gen
> ///////////////////////////////////////////
> For Density of State calculation we have to shift our geometry to Unitcell.
>  28  S
>   C  H
>     1 2      0.98140000      1.04655000      0.00000000
>     2 1      1.54350100      1.97980000      0.00000000
>     3 1      0.85434800      3.22200000      0.00000000
>     4 1      1.52784100      4.44910000      0.00000000
>     5 1      0.83841700      5.70995000      0.00000000
>     6 1      1.52558700      6.93745000      0.00000000
>     7 1      0.85861600      8.16790000      0.00000000
>     8 1      1.55011300      9.44240000      0.00000000
>     9 1      0.88311300     10.67285000      0.00000000
>    10 1      1.56219600     11.92150000      0.00000000
>    11 1      0.86961700     13.18065000      0.00000000
>    12 1      1.52639800     14.42235000      0.00000000
>    13 1      0.76925600     15.62445000      0.00000000
>    14 2      1.44626500     16.47830000      0.00000000
>    15 2      3.49406700      1.00195000      0.00000000
>    16 1      2.96557000      1.95460000      0.00000000
>    17 1      3.69848600      3.17155000      0.00000000
>    18 1      3.00933300      4.41370000      0.00000000
>    19 1      3.70284500      5.69035000      0.00000000
>    20 1      3.02619500      6.93325000      0.00000000
>    21 1      3.69503000      8.16930000      0.00000000
>    22 1      3.00756000      9.44100000      0.00000000
>    23 1      3.67642400     10.67705000      0.00000000
>    24 1      2.99974500     11.91995000      0.00000000
>    25 1      3.68177400     13.20275000      0.00000000
>    26 1      3.00338200     14.40000000      0.00000000
>    27 1      3.60368600     15.68735000      0.00000000
>    28 2      2.82484200     16.44975000      0.00000000
>        0.00000000      0.00000000      0.00000000
>      5.009544167      0.00000000      0.00000000
>       0.00000000     50.00000000      0.00000000
>       0.00000000      0.00000000     50.00000000
>
>
> 2- Run this input and geometry.
>
>     Look for Fermi Energy Level.
> Fermi energy:                    -0.1837716172 H       -5.000680 eV
>  Band energy:                    -43.6825057076 H    -1188.661459 eV
>  TS:                               0.0000000000 H        0.000000 eV
>  Band free energy (E-TS):        -43.6825057076 H    -1188.661459 eV
>  Extrapolated E(0K):             -43.6825057076 H    -1188.661459 eV
>
>
>  Energy H0:                        0.0000000000 H        0.000000 eV
>  Total Electronic energy:        -43.6825057076 H    -1188.661459 eV
>  Repulsive energy:                 1.4070475536 H       38.287712 eV
>  Total energy:                   -42.2754581540 H    -1150.373747 eV
>  Total Mermin free energy:       -42.2754581540 H    -1150.373747 eV
>
>  Calculation with static geometry
>
>  Non-SCC calculation
>
>
> 2- For proper dos.dat plotting we have to use 2 scripts :
>
>  band2dat and dosplot.in
>
>
> a)  band2dat -N dftb_in_dos.band.out band.dat
> b)   for dosplot in:
>
>  [gauss]
> coefficient = 0.2
> exponent = 20.0
> [data]
> nr_kpoints = 50   #change this which k point you want to calculate
> kweights =  1.000000
>
> eigenvalues = << band.dat   !!!! not dftb_in_dos.dat
> eigval_order = k_major
>
>  dosplot dosplot.in > dos.dat      if you run from your folder "bin"
>
> 3-  and to plot:
> xmgrace dos.dat
>
> Now here is my question is coming. In this geometry there should be
> confused Fermi Energy Level or I am calculating in wrong way? So which Fermi
> Energy Level in this DOS graphics should be done. From detailed.out file we
> can say:  Fermi energy: -0.1837716172 H       -5.000680 eV. To shift +Efermi
> Level or -Efermi Level or just draw this plot between -4  to 4 or what could
> be other solution? For my further calculation I have to get proper Fermi
> Energy Level and DOS graphs.
>
> Thank you for support
>
> Ezgi
>
>
>
>
>
>
>
>
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